Unless otherwise indicated herein, the information described in this section is not prior art to the claims and is not admitted to be prior art by inclusion in this section.
Various types of hearing prostheses provide people with different types of hearing loss with the ability to perceive sound. Hearing loss may be conductive, sensorineural, or some combination of both conductive and sensorineural. Conductive hearing loss typically results from a dysfunction in any of the mechanisms that ordinarily conduct sound waves through the outer ear, the eardrum, or the bones of the middle ear. Sensorineural hearing loss typically results from a dysfunction in the inner ear, including the cochlea, where sound vibrations are converted into neural signals, or any other part of the ear, auditory nerve, or brain that may process the neural signals.
People with some forms of conductive hearing loss may benefit from hearing prostheses such as hearing aids or vibration-based hearing devices. A hearing aid, for instance, typically includes a small microphone to receive sound, an amplifier to amplify certain portions of the detected sound, and a small speaker to transmit the amplified sounds into the person's ear. A vibration-based hearing device, on the other hand, typically includes a small microphone to receive sound and a vibration mechanism to apply vibrations corresponding to the detected sound directly or indirectly to a person's bone or teeth, thereby causing vibrations in the person's inner ear and bypassing the person's auditory canal and middle ear. Examples of vibration-based hearing devices include bone-anchored devices that transmit vibrations via the skull and acoustic cochlear stimulation devices that transmit vibrations more directly to the inner ear.
Further, people with certain forms of sensorineural hearing loss may benefit from hearing prostheses such as cochlear implants and/or auditory brainstem implants. Cochlear implants, for example, include a microphone to receive sound, a processor to convert the sound to a series of electrical stimulation signals, and an array of electrodes to deliver the stimulation signals to the implant recipient's cochlea so as to help the recipient perceive sound. Auditory brainstem implants use technology similar to cochlear implants, but instead of applying electrical stimulation to a person's cochlea, they apply electrical stimulation directly to a person's brain stem, bypassing the cochlea altogether, still helping the recipient perceive sound.
In addition, some people may benefit from hearing prostheses that combine one or more characteristics of the acoustic hearing aids, vibration-based hearing devices, cochlear implants, and auditory brainstem implants to enable the person to perceive sound.